Blunt tip needles have been found to be effective tools in the on-going battle to control the spread of infectious agents borne in body fluids when used in a generally recognized control program including the use of double gloves, appropriate protective clothing and face shields, appropriate needle packaging, and special packing and disposal techniques for used needles. It is widely known that infectious bacterial and viral diseases such as H.I.V., hepatitis, various venereal diseases, etc., can be spread through contact with the body fluids of infected individuals. The Occupational Health & Safety Administration (O.S.H.A.) has recently promulgated regulations governing the exposure of workers to infectious agents. The regulations are concerned, in part, with the transmission of infectious agents by puncture wounds or cuts from various sharp medical devices which have been contaminated with body fluids potentially containing infectious agents, e.g., hypodermic needles, catheters, etc.
It is known that a surgeon during the course of a major operation may sustain one or more needle sticks when suturing with a surgical needle. In addition, support personnel are also exposed to potential needle sticks when handling surgical needles having sharp piercing points.
Blunt tip surgical needles were developed over thirty years ago for use with certain friable tissue, such as the kidney. More recently, their use to prevent needle sticks as part of a multi-faceted program to prevent the spread of infectious agents has become accepted in the medical field. The blunt tip needles of the prior art, however, were known to have problems penetrating through tough tissues and could only be used on certain types of soft tissues.
As previously mentioned, there is a heightened concern regarding the spread of infectious diseases caused by contact with infectious body fluids. Consequently, the medical community has now demanded that surgical needle manufacturers supply blunt tip needles useful in many types of tissue (in addition to friable tissue) as part of their infectious disease control programs. In order to provide blunt tip taper point needles which approach the penetration characteristics of conventional taper point needles (having sharp piercing tips) and which have utility on various types of tissue, it has been necessary to decrease the radius of the points of blunt tip needles. However, it is known that such blunt tip needles having improved tissue piercing characteristics are difficult to manufacture compared to conventional blunt tip needles which are designed for use with friable tissue.
Blunt tip surgical needles are manufactured using several conventional processes, for example, a lathe-type process. In such processes, a conventional wire is cut into blanks which are fed into a lathe, screw machine or similar apparatus. A tool spins or orbits about the distal end of each wire blank to form a blunt end or tip having a desired profile. However, it is known that conventional blunt tip manufacturing processes have several deficiencies. A major deficiency relates to dimensional instability. This is believed to be caused, at least in part, by the cutting tools wearing out rapidly. This condition worsens when cutting blunt tip needles having smaller tip radii. For example, two cutting tools are conventionally used in a particular conventional blunt tip needle manufacturing process. One tool forms the proximal section of the taper, and one tool forms the distal, blunt profile, piercing tip. It is possible for the two cutting tools to be out of synchronization resulting in the manufacture of needles having out of specification needle and tip profiles. Yet another deficiency associated with conventional blunt tip manufacturing processes relates to the limitation on the types of alloys which can be processed with conventional cutting tools. In particular, it is known that hard alloys wear out cutting tools very quickly. Still yet another deficiency associated with existing blunt tip manufacturing processes is the slow throughput of machinery used in such processes when compared with conventional sharp taper point needle manufacturing processes.
Therefore, what is needed in this art is a process for manufacturing blunt tip needles which is efficient and economical, which reduces dimensional variability, which can be readily used on a multitude of alloys, and which eliminates the need for cutting tools to produce blunt tips.